Solid paints

Abstract

Solid paint compositions having dimensional stability based on ion bonding are formed by interaction of certain polymers, having acid group functionality and dissolved in non-polar solvents, with a substantial excess in the order of 100-600 mole percent of a cross-linking reactant formed by solution of a metal hydroxide, ammonium hydroxide or cation former in a polar solvent of dielectric strength greater than 10.

What is claimed is: 
     
       1. A solid paint composition having dimensional stability based on ion bonding comprising the admixture of: a. a solution of a curable polymer resin having a molecular weight ranging from 1,000 to 7,000 and sufficient reactive acid functional groups selected from the group consisting of carboxylic, sulfonic and phosphonic to provide an acid number from 20 to 80, said resin dissolved in a non-polar solvent to provide a 25 to 90 weight percent solution;   b. a solution or suspension of a metal hydroxide, ammonium hydroxide or organic cation former in a polar solvent of dielectric strength greater than 10 to provide a 10-50 weight percent solution, said metal hydroxide selected from the group consisting of sodium, potassium, lithium, barium, calcium, manganese and magnesium;   c. a metallic drier in amounts from about 0.5 to 5 weight percent based on the total weight of polymer; wherein said composition contains metal hydroxide, ammonium hydroxide, or organic cation former in excess of, from 100 to 600 mole percent, the amount required to neutralize said reactive acid group of the resin.     
     
     
       2. The composition of claim 1 wherein the polar solvent is selected from the group consisting of a C 1-8  aliphatic alcohol, formamide and water, the metal hydroxide is sodium hydroxide, and the functional group is a carboxylic acid group. 
     
     
       3. The composition of claim 2 wherein the aliphatic alcohol is methanol. 
     
     
       4. The composition of claim 2 wherein the resin is a polyester resin. 
     
     
       5. The composition of claim 2 wherein the resin is an alkyd resin. 
     
     
       6. The composition of claim 4 wherein the polyester resin having a molecular weight of 1500-3500 and acid number 38-48 is dissolved in mineral spirits and the sodium hydroxide is present at 220-280 mole percent. 
     
     
       7. The composition of claim 2 having from 1 to 3 weight percent of organic acid metal salt drier, said metal being selected from the group consisting of cobalt, zinc, magnesium, aluminum, manganese and zirconium. 
     
     
       8. A process for preparing a solid paint having dimensional stability based on ion bonding and a gel strength from about 100 to 190 which comprises: a. dissolving a resin having pendant or terminal reactive acid groups selected from the group consisting of carboxylic, sulfonic and phosphonic in a non-polar hydrocarbon solvent in the range of 25 to 90 weight percent, said resin having an acid value in the range of from 20 to 100;   b. mixing pigments, fillers, colorants and 0.5 to 5 weight percent of an organic acid metal salt drier into the resin solution;   c. adding thereto under vigorous stirring a 20 to 30 weight percent solution of suspension of metal hydroxide, ammonium hydroxide, or organic cation former in a C 1-8  aliphatic alcohol containing in excess of, from 100 to 600 mole percent, the amount required to neutralize said reactive acid group of the resin.   
     
     
       9. The process of claim 8 wherein the resin is a homopolymer or copolymer selected from the group consisting of alkyd resin, polyester, unsaturated polyester, polyolefin, polystyrene, polyvinylchloride, polymethacrylate, polyacrylate, or mixtures thereof, wherein said reactive acid group is a carboxylic acid group. 
     
     
       10. The process of claim 9 wherein 210-250 mole percent of a 25 weight percent solution of sodium hydroxide in methanol is combined with a polyester resin. 
     
     
       11. The process of claim 10 wherein the resin is an alkyd resin having a molecular weight of 1500 to 3500 and an acid number of from 38 to 48. 
     
     
       12. A solid paint prepared according to claim 8. 
     
     
       13. A solid paint prepared according to claim 11. 
     
     
       14. A paint stick which comprises the solid paint of claim 12 encased in a removable skin.